Jeff's comment (the latter part is relevant):
When a non-default toolbar is enabled in the main window, the existing toolbars
(like File, Edit) are moved to the right and the recently enabled toolbar (like
Memory or Debug) are placed at the left.  When you turn these off, the space
that was reserved to show the toolbar is retained, and therefore all of your
default toolbars have been shifted to the right.

Position is extremely important when it comes to toolbars, so shifting them on
the user is NOT desired.  It is also not good to have gaps between the toolbars,
unless the user has explicitly created them by moving the toolbars via the mouse.


In sum: If first toolbar in a row is made invisible, there remains an empty
space. The resulting perception isn't nice, user needs to move the toobars by
hand. Those should be aligner automatically to take the free space in front of them.